How can you tell the difference between "simple" and "compound" events? I'll give 5 examples


*

*Getting a sum of 10 in a toss of 2 dice

*Getting a hand of 8 cards consisting of 3 aces and 5 face cards

*Seating 7 persons in a row, 2 of whom should sit together

*Getting at least 2 heads in a toss of 4 coins

*Getting 2 red balls from a box containing 5 red balls and 6 blue balls
I believe 1, 3, and 5 are simple events, while 2 and 4 are compound events
But my problem is that I cannot tell if this is true or not, I'm uncertain of whether an event is simple or compound. How can I tell the difference?
 A: I looked up the definition of compound event and found my original comment was wrong, but I think I can explain compound event now:
Simply stated, a simple event can happen only one way (has only one simple outcome) whereas a compound event can happen multiple ways (it's a subset of the sample space consisting of more than one simple outcome).
An easy example: The experiment is roll a single die. The sample space (set of all possible simple outcomes) is {1,2,3,4,5,6}. The event '$E$=getting a number more than two and less than four' is a simple outcome, as it can only happen if you get 3 on the die, $E$={3}. However, the event '$F$=getting an even number' is a compound event, because if you get 2, 4 or 6 then the event happens, $F$={2,4,6}.
From this definition, you can show that all of your above example are compound events.
Event 1 = {(4,6),(5,5),(6,4)} three simple outcomes so compound.
Event 2 has $\binom 4 3*\binom {12} 5$ simple outcomes, one of which is aces of diamonds, hearts and clubs, all the jacks, and king of hearts. (I'm assuming this is choosing 8 cards from a standard deck without replacement.)
etc.
Edit: By the way, things do get a bit messy. Let me give an example. Another possible sample space for rolling a die is {even,odd}. It is not useful for finding the probability of rolling a number less than 2, but it works if we want to know the probability of getting an even number. So is the event getting an even number really compound? Shrug.
